Worked on the openmfp/portal-ui-lib repository to address a security vulnerability in the navigation header by sanitizing user-generated names, effectively preventing Cross-Site Scripting (XSS) attacks. The solution involved implementing robust input sanitization using JavaScript and TypeScript, ensuring that potentially malicious HTML content could not be rendered. To validate the fix, automated unit tests were added, focusing on both security and code quality. This work strengthened the security posture of the portal UI library, which is used across multiple applications. The approach demonstrated attention to detail in front end development, security best practices, and comprehensive testing methodologies within a collaborative environment.